The invention relates to a water nozzle comprising at least two separate water supply devices through which, in a controllable fashion, different water volume flows can be supplied, wherein the water volume flows are combined at a flow head to an annular jet. By controlling the volume flows, a slim jet or at least a widened jet can be alternatively generated. Such a water nozzle is disclosed in WO 2014/166563 A1 and comprises at least two separate water supply devices through which, independent of each other, different water volume flows are supplied to a flow head. At the flow head, the water volume flows are combined to an annular jet. Depending on which one of the volume flows is greater, a slim bundled annular jet or a more or less widened annular jet is produced.
In practice, for generating water fountain display effects, there is the need for water nozzles that can shut off the generated water jet abruptly. This is realized by mechanical shut-off devices, so-called shutters, that shut off the water supply within the nozzle device and temporarily prevent water from exiting.
WO 2005/078289 A1 discloses a different construction in which a water jet, by means of independently switchable air supply valves, can be deflected into different channels so that a similar effect can be generated.
Both devices are however limited with regard to the water jet display throw because the aforementioned devices require a very expensive and complex configuration for high water pressures; such a configuration moreover requires intensive maintenance and is prone to wear. The configuration of WO 2005/078289 furthermore is subject to physical limitations with regard to the employable water pressure.